Disc Displacement Without Reduction Research Articles

Arthroscopic anatomy of the anteromedial wall of the temporomandibular joint: Implications in articular disc displacement

Numerous anatomical and imaging studies have established a close relation between disc displacement of the temporomandibular joint (TMJ) and the medial wall of the TMJ. These studies have revealed a direct association between disc displacement without reduction (DDWoR) and the occurrence of fatty degeneration within the superior fascicle of the lateral pterygoid muscle (SPLM). While the aetiology of this phenomenon remains unclear, it has been suggested that it stems from the interaction between this muscle fascicle and the bony surface of the medial wall of the joint.

Pain, Function and Quality of Life in Temporomandibular Disorder Patients With Different Disc Positions.

Whether pain, jaw function and quality of life are correlated with disc positions is controversial, and similar studies evaluating disc positions by magnetic resonance imaging (MRI) are very limited. This study evaluated the pain, mandibular function and quality of life of the temporomandibular disorders (TMDs) patients with different disc positions according to MRI, and the relationship among them. Three hundred and thirty-five participants were included. Patients completed questionnaires included the Numeric Rating Scale (NRS), Jaw Functional Limitation Scale 8-item (JFLS-8), the Generalised Anxiety Disorder 7-item (GAD-7), Patient Health Questionnaire 9-item (PHQ-9) and Oral Health Impact Profile for TMD (OHIP-TMD). MRI was conducted to evaluate these diagnoses, resulting in the identification of three distinct categories: normal positioning (NP), disc displacement with reduction (DDwR) and disc displacement without reduction (DDwoR). Participants had the mean age of 28.55 ± 11.10 years (80.90% women). DDwR and DDwoR had a higher percentage of females compared with NP. Significant differences existed among patients in all questionnaires. The DDwoR group had significantly the highest pain, functional limitation and the worst quality of life. Moreover, they experienced the most difficulties in chewing tough foods, yawning, experiencing pain and psychological discomfort. Moreover, the multivariate regression showed that age, female gender, diagnosis as DDwoR, GAD-7 and PHQ-9 were significantly linked to higher functional limitation. Worse quality of life was associated with age, diagnosis as DDwoR, GAD-7 and PHQ-9. Among patients with different disc positions, DDwoR showed the highest pain, functional limitation and the worst quality of life. Also, NP showed a proportion of chronic pain. Physical pain, psychological discomfort and chewing tough food were regarded as the most impaired. Women who experience anxiety and depression tended to have a higher propotion of dysfunction and a lower quality of life.

Cone beam computed tomography evaluation of condyle position and joint space in a group of intra-articular disorders patients undergoing stabilization splint treatment

This cross-sectional study assesses condyle position and joint space using Cone Beam Computed Tomography (CBCT) in patients with intra-articular disorders undergoing stabilization splint treatment. Patients are categorized into three groups based on MRI findings: no disc displacement (no DD), disc displacement with reduction (DDwR), and disc displacement without reduction (DDwoR). The study involves 35 patients, each with at least one DDwR joint. CBCT evaluates joint space and condyle position, revealing wider anterior, posterior, and superior joint spaces in both DDwR (anterior: 2.48 ± 0.98mm; posterior: 1.83 ± 0.71mm; superior: 2.46 ± 0.81mm) and DDwoR groups (anterior: 2.41 ± 1.13mm; posterior: 2.65 ± 1.14mm; superior: 2.74 ± 0.88mm) compared to the no DD group. Posterior condyle position accounts for the highest prevalence, at 60.4%, in DDwR joints. While no significant difference is noted in condyle position and anterior and superior joint space among three groups, a significant difference is observed in posterior joint space between groups (p < 0.05). The study suggests that joint space may be greater in joints with disc displacement, and posterior condyle position likely predominates in joints with and without disc displacement. However, further research is needed due to the small sample size.

Comparative study of arthrocentesis with concentric-needle cannula with classic concentric needle: A randomized single-blind controlled clinical trial

This study aimed to assess and compare the efficacy of two distinct single-puncture techniques in temporomandibular joint (TMJ) arthrocentesis for managing disk displacement without reduction (DDwoR).Sixty patients with DDwoR were randomly and blindly assigned to two treatment groups (n = 30 each): group 1 — TMJ arthrocentesis with the classic concentric needle; and group 2 — TMJ arthrocentesis with the concentric needle-cannula system. The following variables were recorded and compared across the groups: patient's pain perception (visual analog scale — VAS, 0–10); maximal interincisal distance (MID, mm); facial edema (FE, presence or absence); and operation duration (OP, minutes).Patients in group 2 presented significantly lower values of VAS score and presence of FE (p < 0.05) when examining the data at 24 and 48 h after the arthrocentesis. They also showed an increase in MID values (p = 0.024) after 6 months. With regard to OP, no significant difference was observed between the groups.Performing a single-puncture TMJ arthrocentesis using a concentric needle-cannula system significantly reduced the patients’ pain perception, and mitigated the presence of facial edema during the immediate postoperative period (at 24 and 48 h). Furthermore, it resulted in a notable increase in the MID after 6 months.

Effect of the application of digital technology-assisted optimization in the process of adjusting jaw position.

The aim of this study was to demonstrate a novel jaw position adjustment technique derived from digital twins and evaluate the application effect of digital technology-assisted optimization in the process of adjusting jaw position on patients with temporomandibular disorders (TMD). A total of 74 patients with TMD who attended the Department of Temporomandibular Joint, West China Hospital of Stomatology, Si-chuan University, between June 2022 and May 2023 were selected. The patient's initial computed tomography (CT) and bilateral temporomandibular joint data obtained by magnetic resonance imaging (MRI) were collected. The 148 joints were divided into the normal disc-condyle relationship (N) group, disc displacement with reduction (DDWR) group, and disc displacement without reduction (DDWoR) group. Assisted by digital technology, the patient's CT data were reconstructed, and a personalized reference plane was established to adjust the jaw position. A three-point bite guiding splint was designed by the adjusted occlusal space and then fabricated by 3D printing technology. It was worn by the patients and then reviewed by MRI. Before and after the adjustment of jaw position, the amount and direction of condyle and disc displacement and the angle between condyle and disc were measured as the evaluation indexes of the effect of the adjustment. The correlation with condylar displacement was evaluated. In the N group, the disc moved backward and downward along the X and Z axes by (-0.60±0.62) and (0.51±0.71) mm, respectively. In the DDWR group, the disc moved backward and upward along the X and Z axes by (-1.33±1.38) and (-0.09±1.31) mm, respectively. In the DDWoR group, the disc moved forward and downward along the X and Z axes by (0.49±1.76) and (1.35±1.76) mm, respectively. The angle between the condyle and the disc decreased after adjustment of the jaw position in all three groups. All patients showed improvement in symptoms after adjustment. Digital technology-assisted jaw position adjustment can simplify the process, reduce the sensitivity of the technique, and improve patients' disc-condyle structure and symptoms. Therefore, its application in the treatment of patients with TMD is of great clinical significance.

The benefits of performing temporomandibular joint arthrocentesis with catheters and a vacuum pump: A randomized control trial

This study aims to compare the effectiveness of two different techniques of double puncture arthrocentesis with and without the addition of catheters and a vacuum pump for management of temporomandibular joint (TMJ) disc displacement without reduction (DDWOR). A total of 48 patients with DDWOR were randomly and blindly allocated into two treatment groups (N = 24): Group 1, TMJ arthrocentesis with the addition of catheters and a vacuum pump to the second needle; Group 2, TMJ arthrocentesis without any addition device. The following variables were registered and compared between groups: patient's pain perception (visual analogue scale [VAS; 0–10]); maximal interincisal distance [MID; mm]; joint effusion (JE, presence or absence); facial edema (FE; presence or absence); and the operation duration (OP; minutes). Patients in Group 1 presented with significantly lower VAS scores (p < 0.001) and presence of FE (p = 0.03) in the post-operative period, also an increase in MID values (p = 0.026), and a reduction in JE (p = 0.022) after 3 months. Besides that, in this group, the procedure was performed significantly faster (p < 0.001). Performing arthrocentesis with the addition of a vacuum pump makes the procedure faster and yields better results in terms of pain, facial swelling, mouth opening and joint effusion.

Clinical study of magnetic resonance imaging-based texture analysis and fasciculation of the lateral pterygoid muscle in young patients with temporomandibular disorder

We aimed to evaluate the effectiveness of clinical examination combined with texture analysis of magnetic resonance imaging (MRI) and fasciculation patterns of the lateral pterygoid muscle (LPM) in distinguishing among the different anatomic causes of temporomandibular disorder. We divided the patients into four groups: healthy control (HC), disk without displacement (DWoD), disk displacement with reduction (DDWR), and disk displacement without reduction (DDWoR). Demographic information and clinical symptoms of patients in each group were recorded. LPM textures were compared among groups. LPM fasciculation was examined. P<0.05 indicated significant difference. Several clinical symptoms and signs, but not age or sex, differed significantly among groups. Oblique sagittal planar MRI revealed significant differences in the parameters of Angular Second Moment, Contrast, Correlation, Inverse Difference Moment, and Entropy between the healthy controls and the 3 patient groups. MRI of the patients, both without and with disk displacement, demonstrated relative uniformity in gray distribution and correlation of gray values, with greater complexity but an unclear texture and no obvious regularity. The proportion of type B LPM fascicles was significantly higher in the DDWR and DDWoR groups CONCLUSION: Temporomandibular disorder, without and with disk displacement, is associated with clinical symptoms and texture analysis values that differ from healthy muscle. The types of LPM fascicles are related to the position of the articular disk.

Comparison of the Efficacy of Two Protocol Treatments in Patients with Symptomatic Disc Displacement without Reduction: A Randomized Controlled Trial.

The aim of this study was to compare the effectiveness of arthrocentesis followed by hyaluronic acid infiltration treatment (ASH) and mandibular exercise therapy (MET) in patients with symptomatic disc displacement without reduction (DDwoR) by examining pain intensity (VAS), mandibular range of motion (MO), and quality of life (QoL). Fifty-two patients were randomly allocated into two groups, MET (N = 26) and ASH (N = 26), and therapy was applied at the baseline and one month after. Patients were followed up at 1 and 12 months after the baseline assessment. Clinical and patient-reported outcomes were compared at the baseline, 1-month follow-up, and 12-month follow-up. The study found no significant differences in VAS and MO between the ASH and MET groups at the baseline. However, while not significant, it was noted that the ASH group showed higher values for MO. Regarding OHIP-14 at 1 month of follow-up, the ASH group showed significant improvements in physical pain (p > 0.01), physical and psychological disability (p = 0.043 and p = 0.029), and handicap (p = 0.033). At the 12-month follow-up, the ASH group showed significant improvements in functional limitation, psychological discomfort, psychological disability, and handicap (p = 0.008, p = 0.001, p = 0.001, p = 0.005, respectively). ASH treatment did not reduce pain or improve mandibular range of motion more than physical therapy in patients with symptomatic DDwoR. However, ASH could be preferable given its positive long-term effects on patients' quality of life. The clinician's main objective is to prioritize the treatment plan order with a focus on the patient's quality of life. Accordingly, healthcare professionals should consider ASH as a treatment option for patients with symptomatic DDwoR who desire long-term improvement in their quality of life.

Stomatognathic Risk Factors and Clinical Manifestations of Temporomandibular Disorders in Indian Population: A Case-control Study.

This study was aimed to compare the risk factors and associated clinical manifestations of patients with temporomandibular disorders (TMDs) in the Indian population. A total of 52 patients were explored according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and compared with 48 controls. The mean age of the study group was 30.96 ± 11.60 years, 41% were males and 59% were females. The mean age in the control group was 31.5 ± 9.9 years (37.5% males), measuring differences in TMD risk factors (self-perceived stress, parafunctions, occlusal interferences, history of orthodontic treatment, and/or extraction). The most common sign observed in the selected subjects was the joint sound (clicking) (42%), followed by mandibular deviation 39% as the second most common sign. Myofascial pain (MFP) (single or multiple diagnoses) was the most frequent diagnosis (n = 40, 76%), followed by disc displacement with reduction (DDWR) (32.1%), arthralgia (30%), and disc displacement without reduction (DDWoR) (7.6%). More than one DC/TMD diagnosis was established in 63.2% of the patients. The risk factors like presence of clenching, stress perception, parafunctions, tooth wear, and occlusal interferences were significantly more frequent in all the cases than in the respective controls. In the studied population, the presence of TMD was found to be positively related to factors namely female gender, parafunction, occlusal interferences, psychological stress, and tooth wear. Myofascial pain is the commonest diagnosis (either single or in combination). It is followed by DDWR (either single or in combination with others). Double diagnosis is also common. Temporomandibular disorders showed a female predilection and were found to be positively related to factors, viz., parafunction, occlusal interferences, stress, and tooth wear. Clinicians should also be aware of common clinical manifestations of TMDs and their related stomatognathic risk factors to provide comprehensive oral care and to identify such factors for disease prevention.

Does Temporomandibular Joint Magnetic Resonance Imaging Diagnosis Support Clinical Examination Diagnosis Following Diagnostic Criteria for Temporomandibular Disorders?

The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) has been validated as a clinical diagnostic guideline with high-sensitivity and -specificity in identifying TMDs. The purpose of this study was to evaluate the agreement between DC/TMD diagnoses and magnetic resonance imaging (MRI) diagnoses in patients with TMD. A prospective cohort study was conducted on patients with TMD. The predictor variable was the clinical diagnosis of TMD based on DC/TMD criteria. The outcome variable was the MRI diagnosis of TMD. The diagnoses used for both the predictor variable and the outcome variable were the same. They were normal, disc displacement with reduction (DDWR), DDWR with intermittent locking, disc displacement without reduction (DDWOR) with limited opening, DDWOR without limited opening, degenerative joint disease, and subluxation. Age and gender of the patients and number of joints evaluated were covariates. Each subject had clinical examination performed by two independent Oral and Maxillofacial Surgeons. All subjects had a bilateral temporomandibular joint (TMJ) MRI performed which was evaluated by a radiologist. The correlation between the clinical and MRI diagnoses was calculated using Cohen's kappa value with a P value of <.05 considered significant. A total of fifty patients (100 TMJs) were enrolled with 38 females and 12 males. The mean ages were 31.92 and 31.75years, respectively, with a total of 100 TMJs analyzed. Internal derangement was clinically identified in 76% of the joints and with MRI in 69% of joints. The Cohen's kappa value between DC/TMD and MRI diagnoses was found to be κ=0.720 (P<.01). The respective sensitivity and specificity in determining disc position clinically for DDWR was 1 and 0.96; for DDWR with intermittent locking 0.78 and 0.91; for DDWOR with limited opening 0.9 and 0.98; for DDWOR without limited opening 1 and 0.9; for degenerative joint disease 0.63 and 0.97 and for subluxation 0.28 and 1.00. The DC/TMD clinical examination performed well in all types of disc displacement but is less reliable than MRI in detecting the presence of degenerative disc diseases and subluxation.

Does the Use of Injectable Platelet-Rich Fibrin After Arthrocentesis for Disc Displacement Without Reduction Improve Clinical Outcomes?

Many studies have reported the role of arthrocentesis to alleviate symptoms in patients with disc displacement without reduction (DDWoR). Nevertheless, the benefit of injectable platelet-rich fibrin (i-PRF) remains unclear. The aim of this study was to answer the following question: Among patients with DDWoR, do those treated with intra-articular injection of i-PRF after arthrocentesis, when compared to those treated with arthrocentesis only, have better clinical outcomes in terms of pain reduction and improvement of jaw movement? This single-blind randomized, controlled study included patients with diagnosed DDWoR, in the Department of Oral and Maxillofacial Surgery at the School of Dentistry, Ege University, who had localized joint pain and limited range of motion. Patients were treated either with arthrocentesis (AC group) or arthrocentesis in combination with intra-articular i-PRF injection (AC+i-PRF group). The predictor variable was treatment (ie, arthrocentesis with or without i-PRF). The primary outcome variable was pain (visual analog scale). The secondary outcome variables were maximum mouth opening, lateral and protrusive movements. Outcome variables were recorded at pretreatment and at the postoperative 1st, 2nd, 3rd, 6th, and 12th months. Statistical analysis was performed using the Brunner-Langer model, with a significance level P<.05. This study comprised 76 patients (34 females/4 males, mean age 47.2±9.1 for the AC+i-PRF group; 35 females/3 males, mean age 46.8±10.2 for the AC group). The treatment success rate was 73.7% for the AC group and 100% for the AC+i-PRF group (P=.012). Pain levels in the AC+i-PRF group were found to decrease more than the AC group over 12months postoperatively (palpation: -6.9±1.2 vs -5.3±1.3; chewing: -6.9±1.5 vs -5.1±1.7; jaw movements: -6.9±1.1 vs -5.1±1.4). This difference was statistically significant (P<.001). The degree of jaw movement in the AC+i-PRF group was found to increase more than the AC group over 12months postoperatively (maximum mouth opening: 8.0±2.1 vs 4.9±2.0; contralateral: 1.8±0.8 vs 0.2±1.0; ipsilateral: 2.9±1.3 vs 0.8±1.5; protrusive: 2.6±1.1 vs 0.8±1.3). This difference was statistically significant (P<.001). Intra-articular injection of i-PRF after arthrocentesis produced greater improvements in pain reduction and jaw movement when compared to arthrocentesis only. These results indicate that i-PRF used in combination with arthrocentesis is an effective adjunctive treatment.

Correlation Between the Masticatory Muscle Dimensions and Internal Derangement of Temporomandibular Joints Based on Magnetic Resonance Imaging

Background: Temporomandibular joint disorders (TMDs) are the most common cause of non-odontogenic pain in the maxillofacial region. Internal derangement (ID) is one of the most prevalent causes of TMDs, and disc displacement is recognized as the most common ID. The masticatory muscles are among anatomical structures involved in TMDs that may be affected by ID. Objectives: This study aimed to evaluate the correlation between the masticatory muscle dimensions and ID of temporomandibular joints using magnetic resonance imaging (MRI). Patients and Methods: This cross-sectional study was conducted on the MRI images of 145 patients, retrieved from the archives of the MRI diagnostic and research center during 2020 - 2021. The patients were categorized into three main groups of normal disc position (NP) (n = 42), disc displacement with reduction (DDR) (n = 54), and disc displacement without reduction (DDWR) (n = 49). The maximum width and height of the masseter and medial pterygoid muscles and the maximum height and length of the superior and inferior heads of the lateral pterygoid muscle were measured on MRI images for each of the groups. Data were analyzed using t-test, Pearson’s correlation test, ANOVA test, and Tukey’s test (alpha &lt; 0.05). Results: Significant differences were observed between the NP, DDR, and DDWR groups regarding the height (P &lt; 0.001) and length (P &lt; 0.001) of the superior head of the lateral pterygoid muscle; both parameters were significantly higher in the NP group, followed by the DDR and DDWR groups (P &lt; 0.05). The dimensions of masticatory muscles were significantly greater in males than females (P &lt; 0.05), except for the width of the medial pterygoid muscle (P = 0.064). The height of the masseter muscle (r = 0.190, P = 0.022) and the medial pterygoid muscle (r = 0.166, P = 0.046) was significantly correlated with age. Conclusion: Significant correlations were found between the height and length of the superior head of the lateral pterygoid muscle and ID of TMJ; the corresponding values were lower in the DDWR group compared to the DDR and NP groups, respectively.

Comparison of imaging findings of 714 symptomatic and asymptomatic temporomandibular joints: a retrospective study

BackgroundThe correlation between temporomandibular disorders (TMD) and imaging features remains unclear. This study compared the cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) features in the temporomandibular joints (TMJs) with and without TMD symptoms.MethodsThe participants were recruited from the TMJ Diagnosis and Treatment Center from March 2022 to September 2022. Condylar morphology and condylar position were evaluated by CBCT. Disc morphology, disc position, and joint effusion were evaluated by T2-weighted image of MRI. The Chi-Square test and binary logistic regression analysis were carried out.ResultsEighty-two patients with bilateral symptoms, 196 patients with unilateral symptoms, and 79 asymptomatic participants received MRI and CBCT examination. There were significant differences in the distribution of sex, age, condylar morphology, condylar position, disc morphology, disc position, and joint effusion in symptomatic and asymptomatic TMJs (P < 0.05), which showed a positive correlation with symptoms (P < 0.05). In multiple logistic regression, 19–30-year-age group, > 30-year-age group, abnormal condylar morphology, posterior condylar position, disc displacement with reduction (DDWR), and disc displacement without reduction (DDWoR) were found to be statistically significant (P < 0.05). The odds of having symptomatic TMJ were 1.952 higher in the 19–30-year-age group and 1.814 higher in the > 30-year-age group when compared to those aged ≤ 18-year-age group. The odds of having symptomatic TMJ were 2.360 higher in persons with abnormal condylar morphology when compared to those with normal condylar morphology. The odds of having symptomatic TMJ were 2.591 higher in persons with posterior condylar position when compared to those with the normal condylar position. The odds of having symptomatic TMJ were 2.764 higher in persons with DDWR and 4.189 higher in persons with DDWoR when compared to those with normal disc position. The area under the curve of the model was 0.736 ± 0.019 (95% CI 0.700–0.773, P = 0.000), which indicated that the model has a good fitting effect.ConclusionsThe imaging findings of TMJs were significantly different between symptomatic and asymptomatic TMJs. TMD is affected by multiple factors including > 19-year-age, abnormal condylar morphology, posterior condylar position, DDWR, and DDWoR, which could be risk factors for the development of TMD symptoms.Trial registration This study was retrospectively registered on 28/03/2022 and endorsed by the Ethics Committee of Affiliated Stomatology Hospital of Guangzhou Medical University (LCYJ2022014).

Suprafoveal condylar arthroplasty in unilateral disc displacement without reduction – A retrospective study

The aim of this study was to evaluate the efficacy of suprafoveal condylar arthroplasty (SFCA) in the management of patients with unilateral temporomandibular joint (TMJ) disc displacement without reduction (DDWoR). A retrospective study comprising patients who underwent unilateral SFCA for clinically and radiologically confirmed unilateral DDWoR from 2008 to 2020 was conducted. Patients older than 18 years at the time of diagnosis with a minimum of 6 months of unsuccessful non-surgical and minimally invasive management (including diet and life style modification, physiotherapy, appliance therapy, pharmacotherapy, arthrocentesis and arthroscopic lysis and lavage) before undergoing surgery with a minimum of 1 year follow-up post-surgery were included in the study. Patients with other articular and extra-articular causes of restricted mouth opening, prior history of mandibular surgery and/or trauma, growth abnormalities, systemic, metabolic, infective, neoplastic conditions affecting TMJ, including gross occlusal disharmony, untreated existing para-functional habits and bilateral DDWoR, were excluded from the study. Patients were assessed in terms pain on a visual analog scale (VAS), interincisal mouth opening (MO) and subjective assessment of mandibular range of movements including deviation of mouth opening, protrusion and ability for contralateral laterotrusion. 23 patients (10 males and 13 female) were included in the study, with a mean age of 35.09 years and mean follow up period of 37.7 months (range = 12–58; SD = 15.3). The mean pain scores on the VAS reduced from 6.35 preoperatively to 1.13 postoperatively and were found to be statistically significant (p < 0.0001). The improvement of the mean pre-operative mouth opening of 21.83 mm to a mean post-operative mouth opening of 42.09 mm was also found to be statistically significant (p < 0.0001). The subjective improvement in protrusive (p = 0.0003), laterotrusive (p = 0.0005) and opening movements (p = 0.0001) after 1 year were also found to be statistically significant. No patient developed any significant changes in occlusion post-operatively. Four of 23 (17.3%) patients developed transient neuromotor deficit of the temporal branch of the facial nerve. Within the limitations of the study, it seems that SFCA (without addressing the disc) might be an alternative to less invasive treatment approaches, if the latter turned out not to be successful.

Craniofacial Morphology of Temporomandibular Disorder Patients with Different Disc Positions: Stratifying Features Based on Sex and Sagittal Skeletal Pattern.

Disc displacement (DD) appears in the majority of temporomandibular disorder (TMD) patients. The correlation between craniofacial morphology and different disc positions has been underlined, while the craniofacial morphological differences based on sex and sagittal skeletal pattern stratification have been insufficiently studied. In this study, 304 patients with TMD complaints were included and classified into normal position, disc displacement with reduction (DDwR) and disc displacement without reduction (DDwoR) groups according to magnetic resonance imaging. A total of 24 cephalometric measurements, covering the cranial base, vertical relationship, sagittal relationship, mandible position and morphology, and dental relationship, were assessed using lateral cephalograms. A stratified analysis was performed based on the sex and sagittal skeletal pattern. Overall, DD patients had distinctive craniofacial morphological features. The posterior cranial base length and mandibular arc angle were statistically different only in females, while the Y-axis angle, occlusal plane angle and sella nasion point A angle (SNA) might be unique features in males. Skeletal class II had the most statistically different measurements compared to the others. Differences in the Frankfort mandibular incisor angle (FMIA) and saddle angle were especially displayed in skeletal class III patients. The sex and skeletal sagittal pattern could affect the morphological differences in TMD patients with different disc positions.

Efficacy of stabilisation splint and low-level laser therapy for patients with chronic closed lock from non-reducible displacedtemporo-mandibular joint discs: A parallel randomised clinical trial.

Stabilisation splint therapy (SST) and low-level laser therapy (LLLT) are effective-invasive treatment for temporo-mandibular disorder (TMD) patients. However, the specific efficacy of each therapy in patients with chronic closed lock (CCL) from temporo-mandibular joints (TMJ) disc displacement without reduction (DDwoR) remains unknown. The aim of this study was to assess and compare the efficacy of SST and LLLT alone or in combination in patients with CCL from TMJ DDwoR. This parallel randomised clinical trial included 42 patients who were diagnosed with CCL from TMJ DDwoR. Patients were allocated equally and randomly into three treatment groups: group I received combined SST and LLLT, group II received LLLT and group III received SST. Maximum mouth opening (MMO), visual analogue scale (VAS), muscle and joint palpation scores and time required to achieve normal state were evaluated at baseline, 1, 2, 4 weeks, 3 and 6months after the intervention. Data were collected and analysed using SPSS software. Regarding MMO and VAS, a statistically significant improvement was found between group I versus group II and versus group III at all evaluation times. Regarding muscle and joint palpation scores, a statistically significant difference was found between group I versus group III, while non-significant difference was found between group I and group II. A statistically significant faster improvement was found in group I versus group III and versus group II. All treatment modalities can be effective in management of CCL from a TMJ DDwoR cases, but the combined SST and LLLT group seems to provide the best and quickest improvement. NCT05548894.

Observational study investigating the relationship between maxillomandibular characteristics and temporomandibular disc conditions in female patients with a skeletal class III pattern.

The objective of this study was to analyze the relationship between maxillomandibular characteristics and the severity of temporomandibular disc displacement in female patients with a skeletal class III (SKIII) pattern. Fifty-seven samples were included in the study. The evaluation of articular disc conditions was conducted using magnetic resonance imaging, while 25 cephalometric variables from lateral and postero-anterior (P-A) cephalograms were measured to determine their maxillomandibular characteristics. The samples were categorized into three groups based on the articular disc conditions: (1) normal disc position (NDP), (2) disc displacement with reduction (DDwR), and (3) disc displacement without reduction (DDwoR). The relationship between the maxillomandibular characteristics and disc conditions was examined through both basic statistical analysis and multivariate analysis using principal component analysis (PCA). The Kruskal-Wallis and Dunn-Bonferroni tests revealed a significant difference between the groups in terms of the deviation of mandibular characteristics observed on the P-A cephalogram. The DDwoR group exhibited significantly larger menton deviation, ramal height asymmetry index, and total mandibular length asymmetry index compared to the NDP and DDwR groups. Moreover, the PCA successfully extracted all cephalometric variables into eight principal components. Among them, only the principal component related to mandibular asymmetry was able to differentiate the SKIII samples with DDwoR from the other groups. The findings of this study highlight a significant relationship between mandibular asymmetry and the severity of disc displacement, particularly DDwoR, in female patients with a SKIII pattern.

Quantitative volume and area assessment of masticatory muscles through magnetic resonance imaging in patients with temporomandibular joint disorders

To compare volume and surface area measurements of the lateral pterygoid (LPM), medial pterygoid (MPM), and masseter muscles (MM) as calculated on magnetic resonance imaging (MRI) based on the position of the temporomandibular joint disk, mouth position, and patient sex, and to calculate the correlations of the measurements among the muscles. Measurements of muscle volume and area were performed on the MRIs of 51 patients. Wilcoxon, Kruskal-Wallis, and Mann-Whitney U tests were used to calculate the significance of differences in measurements. The Spearman correlation coefficient calculated the correlation of measurements among the muscles. The significance of difference was established at P < .05. Volume and area of the left MPM in patients with disk displacement without reduction (DDWOR) were larger than in patients with normal disk position (P ≤ .040). MM volumes were smaller with DDWOR than with DD with reduction bilaterally (P ≤ .031). The volume and area of LPM and MM were significantly different between closed and open mouth positions (P < .001). Differences in volume and area between females and males were significant for all muscles in volume (P ≤ .021) and for MPM and MM in area (P ≤ .021). Significant positive correlations were found among all muscles for volume and area. Volume and area measurements of the masticatory muscles varied according to disk and mouth position and patient sex and exhibited significant positive correlations.

TMJ &amp; Its role in Prosthodontia: A Systematic Review

Aim The aim of this systematic review was to evaluate importance of TMJ and assessing the prevalence of temporomandibular joint disorders (TMJD) among the general population. Methodology Five main electronic databases and three grey literature were searched to identify observational studies in which TMJD was diagnosed using the research diagnostic criteria (RDC/TMD) or diagnostic criteria (DC/TMD). The studies were blindly selected by two reviewers based on eligibility criteria. Risk of bias (RoB) was assessed using the Joanna Briggs Institute Critical Appraisal Checklist, and the “R” Statistics software was used to perform meta-analyses. Results From 2741 articles, 21 were included. Ten studies were judged at low RoB, seven at moderate, and four at high. The TMJD investigated were as follows: arthralgia, disk displacement (DDs) with reduction (DDwR), DDwR with intermittent locking, DDs without reduction (DDwoR) with limited opening, DDwoR without limited opening, degenerative joint disease (DJD), osteoarthritis, osteoarthrosis, and subluxation. The main results from prevalence overall meta-analyses for adults/elderly are as follows: TMJD (31.1%), DDs (19.1%), and DJD (9.8%). Furthermore, for children/adolescents are as follows: TMJD (11.3%), DDs (8.3%), and DJD (0.4%). Considering the individual diagnosis meta-analyses, the most prevalent TMJD is DDwR for adults/elderly (25.9%) and children/adolescents (7.4%).

Double-Puncture Versus Single-Puncture Arthrocentesis: A Randomized Controlled Trial with 3 Years of Follow-Up.

To compare the clinical effectiveness of conventional double-puncture vs single-puncture type 2 arthrocentesis for management of temporomandibular joint (TMJ) disc displacement without reduction (DDWOR) after 3 years of follow-up. A total of 26 patients with DDWOR were randomly and blindly allocated into two treatment groups (n = 13 each): group 1 = conventional double-puncture arthrocentesis; group 2 = single-puncture type 2 arthrocentesis. Data on gender, side of painful joint complaint, age (years), duration of joint pain (months), maximum interincisal distance (MID, mm), and pain intensity (self-reported with a 0-10 visual analog scale [VAS]) were collected. VAS scores and MID were measured before (baseline) and 3 years after (final) the arthrocentesis. Twenty-three patients completed the study (group 1, n = 11; group 2, n = 12). Both techniques resulted in significantly reduced VAS scores and increased MID (P = .001) after the 3 years of follow-up; however, there were no statistically significant differences between techniques (P > 0.05). The two arthrocentesis methods tested were both effective in reducing VAS scores and increasing MID in patients with DDWOR.